Yes, so for peripheral T cell lymphomas, um, You know, those are the sort of the landscape of the universe of mature T cell lymphomas or or cancers of post thymic T cells, and that really encompasses the spectrum of T cell lymphomas. When when we use the term PTCL sort of colloquially or when talking about patients, we often mean the systemic mature T cell lymphomas and of those, Uh, at least in the US or Europe, the most common, uh, subtypes would be, uh, follicular helper T cell lymphomas, which talk about peripheral T-cell lymphoma, not otherwise specified, which used to be the most common subtype, now is the second most common subtype. And then various forms of anaplastic large cell lymphoma. And then there's about, there's more than 30 entities in the latest WHO. So there are more specific subtypes as we've understood more about the biology or different clinical pathologic entities. But about 2/3 of patients will have one of those three systemic subtypes. And I think when people use the term PTCL, that's often what they mean. Um, historically, we've Approach these with chemotherapy with moderate results. So, uh, what that means to me is that when you give combination chemotherapy and that's chop-based chemotherapy or intensified chemotherapy, adding agents like opposide or more intensive regimens, sometimes consolidating with transplant, a fraction of patients will be cured, cured means it's gone and it never comes back, um. But not anywhere near the numbers we would like. So if we look at historical data or some clinical trial data with COP, uh, we think the long term cure rates are probably between 20 and 30 or 35%, um, not evenly distributed amongst the other subtypes. When amongst the different subtypes, when you intensify that therapy, maybe you push those cure rates up to 40, 45%. So that's high enough that it's been hard to completely abandon chemotherapy because there's a real fraction of patients who are cured, um, but certainly not so high that there's not tons of room for improvement.
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